DTC B15C2: Speed Signal Malfunction: Description

The display and navigation module display receives a vehicle speed signal from the No. 1 meter ECU sub-assembly and information about the navigation antenna, and then adjusts vehicle position.

The display and navigation module display stores this DTC when the difference between the speed information that the navigation antenna receives and the SPD pulse received from the No. 1 meter ECU sub-assembly becomes large.

HINT: 

• A voltage of 12 V or 5 V is output from each ECU and then input to the No. 1 meter ECU sub-assembly. The signal is changed to a pulse signal at the transistor in the No. 1 meter ECU sub-assembly. Each ECU controls the respective systems based on the pulse signal.
• If a short occurs in any of the ECUs or in the wire harness connected to an ECU, all systems in the diagram below will not operate normally.